3. Pyrolysis
Pyrolysis is a thermo chemical decomposition
of organic material in to liquid, gases and
char(solid residue)at elevated temperature in
the absence of oxygen(or any halogen).
4. WHAT IS PYROLYSIS?
Pyrolysis does not involve reactions with oxygen,
water, or any other reagents.
In practice, it is not possible to achieve a completely
oxygen-free atmosphere.
Because some oxygen is present in any pyrolysis
system, a small amount of oxidation occurs.
8. Materials used??
Biomass ;- is an organic material produced
directly from plants & animals or indirectly
from industrial,commercial,domestic or
agricultural products.
Agricultural waste :- crop & vegetabl residuals(rice
husk, straw)
livestock :- butchery waste, bone material, dead
animals.
forestry :- forest residue, processing waste,sawdust.
Fishery :- processing waste, fishbone meal,dead fish.
Industrial & house hold organic residuals :- sewage
sludge, waste food etc.
9. Types of pyrolysis
1. Slow pyrolysis
2. Fast pyrolysis
Dry Pyrolysis
Oxydizing Pyrolysis
10. Slow pyrolysis
Slow biomass heating rates→low
temperatures→lengthy gas and solids
residence times.
Temperature :- around 500˚C.
Main product :- bio-char.
11. Fast pyrolysis
Yield 60% bio-oil.
Takes only seconds to complete the pyrolyses.
Very high heating and heat transfer rates,which
require a finely ground feed.
Residence time of pyrolysis vapours in the
reactor less than 1 sec.
Quenching (rapid cooling) of the pyrolysis
vapours to give the bio-oil product.
Calorific value :- 3500kcal.
13. Dry Pyrolysis
Process of thermal decomposition without
access of oxygen (O₂)
Product of dry pyrolysis are gas with high
heat of combustion, liquid and solid carbon
residue.
Type of dry pyrolysis depend on the
temperature of the process
14. Oxidizing Pyrolysis
It’s impossible to achieve a completely
oxygen-free atmosphere.
Thus, a small amount of oxidation occurs.
If volatile or semi-volatile materials are
present in the waste, thermal desorption
will also occur.
15. Thermal decomposition of industrial waste
by its partial burning or direct contact with
end product of fuel combustion
This method is used for neutralization of
most wastes including “inconvenient” ones
for burning
17. Rice Husk
The outermost layer of the paddy grain is the
rice husk, also called rice hull.
Still often considered as a waste product in
the rice mill & therefore often either burned
in the open or dumped on wasteland.
Rice husk has high calorific value and often
can be used as a renewable fuel.
19. Process
moisture free rice husk sample was taken in
to a perforated holder and was introduced in
to the tube furnace.
The furnace was made air tight & heated
electrically.
Reactor temperature was recorded using a
digital thermometer.
Pyrolyses were performed under
vaccum.(710-720mm Hg).
20. A centrifugal pump was set to create & maintain
the vaccum inside the pyrolyser.
Temperature of pyrolyser was varied within 400-
650°C.
The mixture of liquid & gas was allowed to come
out through vaccum line & set at one side of the
pyrolyser.
The fluid from the pyrolyser was condensed in a
series of ice cooled condenser & bio-oil was
obtained.
21. Uncondensed gas was blown off.
The solid bio-char was collected from the
pyrolyser as residue at the end of each batch
of pyrolysis.
22. Advantages of pyrolysis
Simple.
Low cost technology.
Capable of processing a wide variety of
feedstock's producing gases,biooil,
biochemical & charcoal.
Reduces greenhouse gas emissions and
waste going to landfill .
23. Produces a marketable product
(electricity).
Low risk of water pollution .
Low risk of odours .
High recovery rate of resources .
Minimal risk of health consequences .
Commercially proven technology.
24. Disadvantages
Technology is still evolving.
Market are yet to be developed for char
product and pyrolysis liquid.
25. Bio-oil (Pyrolysis Oil)
dark brown liquid
has a similar composition to biomass.
much higher density than woody materials
which reduces storage and transport costs.
Boilers
Furnaces
Hot Water Generators
Hot Air Generators
Thermic Fluid Heater
Electric Generators (mixed with 50% diesel)
Diesel Pumps(mixed with 50% diesel)
26. Biochar
The growing concerns about climate change have
brought biochar into limelight. Combustion and
decomposition of woody biomass and agricultural
residues results in the emission of a large amount of
carbon dioxide.Biochar can store this CO2 in the soil
leading to reduction in GHGs emission and
enhancement of soil fertility.
can increase the available nutrients for plant growth,
water retention and reduce the amount of fertilizer by
preventing the leaching of nutrients out of the soil.
reduces methane and nitrous oxide emissions from
soil, thus further reducing GHGs emissions.
can be utilized in many applications as a replacement
for other biomass energy systems.
can be used as a soil amendment to increase plant
growth yield.
27. Syngas
made up of carbon monoxide, and
hydrogen (85%) with smaller amounts of
carbon dioxide and methane.
has a high calorific value so it can be used
as a fuel to generate electricity or steam.
may also be used as a basic chemical in the
petrochemical industry.
has less than half the energy density of
natural gas.
28. conclusion
pyrolysis has been attracting much attention
due to its high efficiency and good
environmental performance characteristics.
It also provides an opportunity for the processing
of agricultural residues,wood wastes and
municipal solid waste into clean energy.
In addition,biochar sequestration could make a
big difference in the fossil fuel emissions
worldwide and act as a major player in the global
carbonmarket with its robust, clean and simple
production technology.